Spindle control means for automatic yarn piecing apparatus

ABSTRACT

Spindle rotation at a spinning frame delivery being serviced by an automatic yarn piecing apparatus is controlled by a rotatable disc member which is pivotably movable about two pivot axes to a plurality of different positions of engagement with and disengagement from a continuously rotated drive wheel and the spindle. Movement of the disc is influenced in various desired ways by biasing means acting thereon and by a cam assembly or other control actuator loosely interconnected to the disc&#39;&#39;s bipivot mount.

United States Patent Merck 1 July 4, 1972 54] SPINDLE CONTROL MEANS FOR 3,398,521 8/1968 Bell et al ..57 53 AUTOMATIC YARN PIECING 3,540,200 11/1970 Tsukumo et a1 ..57/34 R 3,546,870 12/1970 Schewe et al. .....57/34 R APPARATUS 3,552,110 1/1971 Livingston ..57/53 [72] Inventor: James K. Merck, Piedmont, S.C.

P E .1 h P t k [73] Assignee'. Maremont Corporation, Chicago, 111. y z zgjgzgi 3 2 ra es [221 Filed: Sept. 10, 1970 [57] ABSTRACT 21 A 1.N.: 70962 l 1 PP O Spindle rotation at a spinning frame delivery being serviced by an automatic yarn piecing apparatus is controlled by a rotata- [52] U.S. Cl. ..57/34 R ble disc member which is pivotably movable about two pivot 51] int. Cl. ..D01h15/00 axes to a pl li y f iff r n p si i n of ngagement with 58 Field of Search ..57/\ R, 34 R, 52, 53, 54 and disengagement from a continuously rotated drive wheel and the spindle. Movement of the disc is influenced in various [56] References Cited desired ways by biasing means acting thereon and by a cam assembly or other control actuator loosely interconnected to the UNITED STATES PATENTS discs bipivot mount. 3,128,590 4/1964 Escursell-Prat ..57/34 R 18 Claims, 11 Drawing Figures P'ATENTEnJuL "4 [972 sum 1 or 6 INVENTOR. 3 1 JAMES MERCK WENTEIJJUL 41912 3,673,780

sum 20F 6 INVENTOR. JAMES K. MERCK PATENTEnJuL 4 m2 3.673.780

sum aor e INVENTOR.

JAMES MERCK WMM PATENTEDJUL 41972 3,673,780

SHEET kllf 6 INVENTOR. JAMES MERCK INVENTOR. JAMES MERCK W w z.

SHEET 5 0F 6 P'A'TENTEDJULE 1912 SPINDLE CONTROL MEANS FOR AUTOMATIC YARN PIECING APPARATUS BACKGROUND OF THE INVENTION This invention relates to automatic yarn piecing apparatus for textile spinning frames and like machines, and more particularly relates to the means employed for controlling spindle rotation at a machine delivery during its servicing by such an apparatus.

It has heretofore been proposed to rejoin, replace or otherwise piece broken yarn at a delivery of a textile spinning frame or like machine by an automatic piecing apparatus: see, e.g., U. S. Pat. No. Re, 26,230 and Japanese Pat. publication 4820/1966. Such apparatuses include a mobile carriage which moves along the spinning frame, either on a continuous patrolling basis or as required on a programmed or demand basis, to a yam-processing delivery at which there exists an end-down or broken-yam condition. The carriage stops adjacent such delivery while servicing mechanisms which it carries eliminate the yarn discontinuity, in any one of several possible ways, and then resumes its movement.

The servicing mechanisms of such a piecing apparatus will frequently include one for interrupting the normal winding rotation of the bobbin-supporting yarn take-up spindle at the machine delivery undergoing servicing. The precise function of any one of the spindle-control mechanisms will depend upon the particular procedure employed for elimination of the yarn discontinuity. In some instances, the mechanism may only be required to halt the normal rotation of the spindle and maintain the same stationary during the servicing operation. This might be the case when, for example, the piecing procedure involves a substitution of bobbins or the travelerthreading of yarn obtained from the spinning machines drafting rolls or from an auxiliary source carried by the piecing apparatus. In other instances it is desirable during each piecing operation for the spindles normal winding rotation first to be halted, then reversed to permit withdrawal of a length of yarn from the bobbin mounted thereon, and thereafter for the spindle to be held stationary while the length of yarn is travelerthreaded and conducted upwardly to the drafting rolls. In still other instances, for example when the piecing operation is performed in the manner disclosed in commonly-assigned and co-pending U. S. Pat. application Ser. No. 846,681 (filed Aug. 1 1969) the spindle preferably is permitted to undergo a limited number of revolutions in the winding direction, to adjust the angularity of the yarn withdrawn from the bobbin during the prior reverse rotation of the spindle in an unwinding direction, before it is held stationary for traveler-threading and other purposes.

The prior art spindle control mechanism, however limited its function, normally includes a member mounted for movement into and out of engagement with some exposed portion of the spindle, usually adjacent its whirl, together with some type of drive means for imparting such movement to the member. When spindle rotation is to be reversed as well as halted, the spindle-engaging member usually takes the form of a rotatable wheel or disc, and some means for imparting rotation to the disc in a direction effective to reversedly rotate the spindle engaged thereby must also be provided. In addition to these basic requirements which are recognized by the prior art, there are various others which, although not as readily apparent, are equally important to the realization of satisfactory operation from a practical, as opposed to merely theoretical, viewpoint.

In the latter connection, a commercially acceptable piecing the apparatus must be relatively inexpensive and highly efficient in operation. Its components must be capable of withstanding possible accidental impacts and the effects of lint and similar airborne foreign materials, and should be readily accessible for repair or maintenance when required; they should also be of such a construction and design as to permit normal maintenance to be done by textile mill mechanics lacking an extensive knowledge of electronics and other technical engineering matters.

In addition to the aforesaid attributes desirably possessed in general by servicing mechanisms of the piecing apparatus, there are additional requirements associated with the spindle control mechanism in particular. Such mechanism should effect the necessary variations in spindle rotation smoothly and unifomily during each piecing operation, so that the timing sequence of the operation will be preserved, the bobbin will remain properly seated upon the spindle, and the stresses imposed upon the spindle and the mechanism will be of desired magnitude. This must be accomplished at each delivery undergoing servicing notwithstanding the possibility of the spindle at such delivery perhaps being slightly out of alignment with the other spindles of the machine or with the piecing apparatus. The inability of some prior art spindle control mechanisms to automatically compensate for such spindle misalignments may result in structural damage and/or failure of the piecing operation. Thus, turning to the aforesaid prior art US Pat. No. Re. 26,230, if the spindle 37 shown in FIG. 5 should, by reason of such misalignment, bedisposed somewhat further along or to one side of the path of pivotal movement of disc member 35, its engagement by the latter might either never occur or, if occurring, be insufficient to effect the desired control of the spindles rotation, either at all or at the time intervals required by the operational sequence of the prior art apparatus. If the misalignment were in another direction, the engagement forces between spindle 37 and disc member 35 may be excessive and structurally damage the spindle, its supporting bearings, or vulnerable components of the prior art control mechanism'such as its cam assembly 31, 32. Apart from the problem of possible structural damage, when the en gagement forces between the control disc and spindle are excessive or are applied abruptly or unevenly to the spindle, an unseating of the bobbin thereon may occur, resulting in failure of the piecing operation.

SUMMARY OF THE INVENTION With the foregoing in mind, the present invention has for its primary object the provision of a spindle control mechanism capable of efficiently and reliably performing any and all of the previously noted spindle-control functions and possessing all of the aforesaid attributes and characteristics necessary for practical commercial operation of a piecing apparatus in a textile mill.

The spindle control mechanism of the invention includes rotatable disc means for controlling spindle rotation, rotational drive means for imparting rotation to the disc means, bipivot mounting means having a fixed pivot axis and a movable pivot axis about which the disc means is pivotally movable relative to the spindle and the rotational drive means, control actuator means loosely connected to the bipivot disc mounting means, and biasing means operable in conjunction with the control actuator means to influence in various desired ways the aforesaid pivotal movement of the disc means. In a preferred embodiment of the invention, the spindle control mechanism is adapted during each piecing operation first to reverse the normal winding rotation of the spindle being serviced, to facilitate the withdrawal of a length of yarn from the bobbin mounted upon such spindle. The mechanism next allows limited rotation of the spindle in its normal winding direction, for the purpose of adjusting the angularity of a portion of the withdrawn length of yarn relative to the bobbin. Then the spindle control mechanism maintains the spindle stationary during traveler-threading of the length of yarn and linkage conveyance of the same upwardly to an elevation adjacent the machine's drafting rolls. To permit the build-up of twist in the upwardly conveyed length of yarn, the mechanism finally disengages from the spindle and permits its resumption of nonnal winding rotation shortly prior to final joining of the yarn ends at the drafting rolls.

The spindle control mechanism herein disclosed is of ex ceedingly compact, reliable, durable and economical construction, being comprised of relatively simple and inexpensive components which are not readily susceptible to damage or failure and which are easily maintained. The mechanism achieves the desired control of spindle rotation rapidly, efficiently and in a uniformly smooth and non-disruptive manner, consistently applying forces of controlled magnitude to the spindles notwithstanding possible misalignments therebetween and/or between any of them and the piecing apparatus.

A specific embodiment of the mechanism, hereinafter described in detail, includes a rotatable disc member adapted for self-aligning engagement with a rapidly and continuously rotated drivewheel and with the spindle at the delivery requiring servicing. The disc member is movable about two relatively displaceable pivot axes between a plurality of positions relative to the spindle and the drive wheel. In one of such positions, occupied intermediate the servicing operations, the disc member is maintained out of engagement with both the spindle and drive wheel, so that it does not then rotate. In a second position of the disc, briefly occupied in this embodiment during the commencement of a piecing cycle of the apparatus, the disc engages and is rapidly rotated by the drive wheel while still being disengaged from the spindle. Without interruption of this rotation, the disc is next moved to a third position wherein it is automatically centered between and is in engagement with both the spindle and the drive wheel. The disc at this time first smoothly and quickly halts and then reverses the normal winding rotation of the spindle, without imposing an overstressing force on any component of the spindle assembly or the control mechanism, even in instances of spindle misalignment. In still another or fourth position, the disc is held in engagement with the spindle but out of engagement with the drive wheel. When in this fourth position the disc permits the spindle to undergo a limited number of revolutions in its winding direction, and thereafter maintains the spindle stationary until just prior to final completion of the yarn joining operation.

The disc member is mounted for the aforesaid movement between its various positions by bipivot means having fixed and movable axes about which the disc is pivotable. Pivotal movement of the disc is influenced by both a spring unit or other biasing means acting thereon, and by a cam assembly or other type of control actuator connected to its bipivot mount. The control actuator is connected to the bipivot mount by a affording a desired degree of lost-motion therebetween. Such linkage enables the actuator to at different times variously produce, initiate and retard pivotal movement of the disc, while allowing the disc a limited but highly important freedom in its pivotal movement under the impetus of the biasing means acting thereon. The freedom of movement afforded the disc, by reason of its bipivot mount and the lost-motion connection of the control actuator therewith, permits desirable self-centering engagement of the disc with the spindle and/or with the drive wheel or both, under controlled force conditions, irrespective of spindle alignment or misalignment.

Although highly efficient and reliable in operation, the present spindle control mechanism is of relatively simple construction. Those of its components which are exposed to the ambient environment are few in number, occupy a minimum amount of space, are easy to manufacture and maintain, and are not readily susceptible to damage from impacts, humidity, or airborne lint and like material. This contributes significantly to the long-termed and trouble-free use of the mechanism under textile-mill conditions.

BRIEF DESCRIPTION OF THE DRAWINGS The foregoing and other features and advantages of the invention will be in part evident and in part pointed out hereinafter in the following description of an illustrative embodiment thereof, which should be read in conjunction with the accompanying drawings, in which:

FIG. 1 is a front elevational view of an automatic yarn piec ing apparatus, mounted upon a fragmentarily-shown textile spinning frame or like machine, having a spindle control mechanism in accordance with the invention;

FIGS. 2-5 are enlarged top plan views of the spindle control mechanism of the apparatus shown in FIG. 1, in positions sequentially occupied byit during a typical cycle of operation, adjacent spindles of the spinning machine and frame portions of the piecing apparatus also being shown, in horizontal section;

FIGS. 5A-5D are views similar to FIG. 5 but showing various alternative embodiments of the spindle control mechanism;

FIG. 6 is a vertical section taken generally along the line 6- 6 of FIG. 5 through the spindle control mechanism; and

FIG. 7 is an enlarged fragmentary horizontal section taken generally along the line 7-7 of FIG. 6 through a portion of the spindle control mechanism.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The spinning machine 10 fragmentarily shown in FIG. 1 is of a conventional multiple-delivery type including a spindle' rail 12 on which are mounted a plurality of rotatable bobbinsupporting spindles 14 to each of which yarn is normally directed from spaced sets of drafting rolls including front delivery rolls 16. The yarn issuing at each delivery from front rolls l6 normally passes downwardly therefrom through a guide 18 and balloon control ring 20, and then through a traveler 22 movable about a spinning ring 24 encircling spindle l4 and the bobbin 26 removably seated upon the spindle. All of the rings 24 on each side of machine 10 are carried by a ring rail 28 which is moved vertically of spindles 14 to guide the yarn axially of bobbins 26 as it is wound thereon byrotation of spindles 14 by drive tapes 30. Tapes 30 normally continuously rotate all of the spindles 14 of machine I0 during its operation, the direction of rotation being dependent upon whether S or Z twist is desired in the finished yarn, and illustratively being in the clockwise (Z twist) direction indicated by the arrows in FIG. 2.

The yarn piecing apparatus 32 shown in FIG. 1 includes a mobile carriage 34 mounted in any suitable manner for movement longitudinally of spinning frame 10 to a position adjacent any delivery thereof requiring servicing by reason of an end-down condition thereat. The carriage includes an open center section disposed between a pair of upright side sections and above an enclosed lower section housing the main drive motor 64 and associated gear box 66 of the apparatus. Various servicing mechanisms, including a spindle control mechanism generally identified by the numeral 36, for effecting repair of the yarn discontinuity are mounted within the open center section of carriage 34 for movement relative to each other and to spinning frame 10. The specific apparatus 32 shown for purposes of illustration is of the type which effects repair of each yarn discontinuity by retrieving and traveler-threading a length of the yam previously spun and wound upon the bobbin 26 at the delivery being serviced, and by thereafter rejoining such yarn with that issuing at the delivery from rolls 16. The spindle control mechanism 36 shown in the drawings and hereinafter described in detail is therefore of a type particularly adapted for cooperation with other carriage-mounted servicing mechanisms 38,40 to effect yarn piecing in the aforesaid manner. It should be clearly understood, however, that principles of the invention are also applicable to piecing apparatus which effect repair of the yarn discontinuity in other ways, as by the addition of a length of seed" yarn, by changing bobbins, and/or by downwardly extending a length of yarn from delivery rolls l6.

SPINDLE CONTROL MECHANISM Referring now particularly to FIGS. 2-6, spindle control mechanism 36 generally comprises spindle engaging means in the form of a disc member 42 supported by a stub shaft 44 for rotation about its central axis and having a band 42' of wearresistant and high-friction material, such as polyurethane, fixedly secured to and extending about its periphery; rotational disc drive means adapted when in driving relationship with disc 42 to impart rotation to it, such drive means including a small drive wheel 46 keyed or similarly secured to one end of a drive shaft 48 (FIG. 6); bipivot means mounting disc 42 for pivotal movement about two pivot axes between a plurality of different positions of peripheral engagement with and disengagement from drive wheel 46 and a spindle l4 undergoing servicing by piecing apparatus 32, such mounting means including a lever arm 50 and crank-like lever member 54 supported by a bracket member 52; resilient disc biasing means in the form of a spring-cartridge unit 56; and control actuator means, consisting of the control cam assembly 60 of piecing apparatus 32, loosely connected to the bipivot disc mount by linkage means 58.

As is best shown in FIG. 6, bracket 52 of spindle control mechanism 36 is of hollow sleeve-like construction and is bolted or otherwise suitably secured at its lower end atop platform 68 of the lower section of carriage 34, in vertical alignment with an opening 69 provided through such platform. Crank-like member 54, which is also generallyof hollow cylindrical construction, projects vertically and coaxially through bracket 52 and beyond its opposite ends, while drive shaft 48 in turn projects coaxially through and beyond crank-like member 54. Suitable bearings positioned therebetween permit pivotal movement of crank-like member 54 relative to bracket 52, about their common central axis, and permit rotative movement of shaft 48 and the drive wheel 46 affixed to the rojecting upper end portion thereof about the same axis and relative to both bracket 52 and member 54. Shaft 48 and wheel 46 are continuously and rapidly rotated during operation of apparatus 32 by means of a pulley 62 secured to the lower end portion of the shaft and connected by a belt 63 to an output shaft of gear box 66 (FIG. 1) of the apparatus. The direction of rotation of wheel 46 is opposite that of spindles 14 of machine 10, i.e., counterclockwise when Z twist yarn is being spun.

The portion of member 54 projecting below bracket 52 is loosely connected by linkage means 58 to control cam assembly 60 of apparatus 32. Assembly 60 includes a cam shaft 60' extending upwardly from the lower section and through one of the side sections of carriage 34 (FIG. 1), and having a cam 60" mounted thereon for controlled counterclockwise rotation during each piecing operation under the impetus of a suitable driving connection between shaft 60 and gear box 66 of apparatus 32. Cam 60" has a camming surface along its peripheral edge, of desired varying profile, which is engaged by a follower 82 of assembly 60. Follower 82 is mounted by a rocker shaft 78 and lever arm 76 for engagement with the edge surface of cam 60", and is biased into such engagement by a spring 80 connected to arm 76 and the frame of apparatus 32. Arm 76 is rigidly connected to rocket shaft 78, such that the movement of follower 82 transpiring upon rotation of cam 60" produces pivotal movement of shaft 78 about its longitudinal axis. Also rigidly connected to shaft 78 is a lever 74 of linkage 58, which linkage further includes an arm 70 fixedly secured to crank-like member 54 and having a yoke 70' at its free end. Yoke 70 loosely receives a stud 72 carried by lever 74, such that the stud is maintained within the yoke but limited relative movement between the two elements is possible. The provision in linkage 58 of such a lost-motion connection, of the foregoing or equivalent type, is significant for reasons hereinafter made apparent.

An end portion of lever 50 is secured to the enlarged upper end portion 54' (FIG. 6) of crank-like member 54, for pivotal movement about an eccentric axis thereof spaced radially from but extending parallel to said member's central axis, by

an upright eccentric-pin 84. Stud shaft 44 extends vertically through and is fixedly supported by the opposite end portion of lever 50. Disc 42 is mounted upon the downwardly projecting lower section of shaft 44, generally in the same plane as drive wheel 46 and accessible portions of the spindles 14, by hub means which permits free rotation of the disc in a clockwise direction about the axis of the stationary shaft, but which limits rotation of the disc in a counterclockwise direction to a predetermined desired amount. As is best shown in FIG. 7, such hub means comprises concentric inner and outer hub elements 85,86 and bearing assemblies 87,88, together with a stop pin 90 carried by and extending radially outwardly from shaft 44 through an arcuate movement-limiting slot 92 provided in inner hub 85. Outer bearing assembly 88 is of the one-way type, permitting free rotation of discsupporting outer hub 86 relative to inner hub in a clockwise direction, but prohibiting relative rotation between the two hubs in a counterclockwise direction. Rotation of inner hub 85 in both directions is permitted by inner bearing assembly 87, but is limited in extent by stop pin 90 and slot 92. Thus, during the free clockwise rotation of spindle control disc 42 permitted by bearing assembly 88, one end 92 of slot 92 abuts pin 90 and maintains inner hub 85 stationary. Upon attempted counterclockwise rotation of disc 42, it and the two hub elements rotate unitarily until the opposite end 92" of slot 92 abuts pin 90. Such latter abutment, which occurs after an approximately l80 rotation when slot 92 is of the exemplary length shown, then prohibits further counterclockwise movement of disc 42.

As is best shown in FIG. 2, spring cartridge unit 56 comprises telescoping inner and outer housing sections 56',56" enclosing a coil spring 94 which biases section 56 in the direction of and outwardly from an open end of section 56", generally to the right as viewed in the drawings. Section 56" is mounted adjacent its opposite end (generally to the left as viewed in the drawings) for pivotal movement about the substantially vertical axis of a pin 57 secured to the frame of apparatus 32. Section 56' has a bore at its free end which receives that portion of stub shaft 44 projecting above lever 50, thus pivotally connecting section 56 and lever 50. Spring 94 exerts a force of predetermined desired magnitude throughout the range of operation of unit 56, which unit is sufficiently well sealed to prevent airborne lint, dust and the like from entering therein.

OPERATION OF THE MECHANISM The FIG. 2 position of the components of spindle control mechanism 36 is that occupied by them intermediate piecing operations and, as is assumed for purposes of present illustration, at the commencement of a piecing operation adjacent spindle 14'. In its fully-retracted position as shown in FIG. 2, disc 42 is out of engagement with both spindle 14' and drive wheel 46 and is therefore stationary, notwithstanding the continuous rotation of wheel 46. Disc 42 is resiliently maintained in such a position by spring unit 56 of the present resilient biasing means, which then biases lever 50 in a counterclockwise direction about the axis of eccentric pin 84. A stop pin 96 carried by and depending downwardly from the inner end portion of lever 50 engages upper end portion 54 of crank-like member 54, preventing counterclockwise pivotal movement of lever 50 beyond its illustrated position. Follower 82 of cam assembly 60 is maintained by spring 80 in engagement with a high-dwell edge segment S1 of cam 60", the rotation of which has just been commenced by cam shaft 60'.

In its subsequent position shown in FIG. 3, disc 42 is in engagement with and being rotated in a clockwise direction by drive wheel 46, but is still out of engagement with spindle 14. Movement of disc 42 from its FIG. 2 and to its FIG. 3 position was initiated by rotation of cam 60" carrying its highdwell segment S1 out of engagement with follower 82, which permitted spring 80 to pivot crank-like member 54in a clockwise direction through levers 76,74, stud 72 and lever 70. Approximately four to five degrees of such pivotal movement of crank-like member 54 shifted lever 50 through a dead-center position wherein the vertical axes of shaft 44 and pins 57,84 became coplanar. As soon as such dead-center position was passed, the moment produced by biasing unit 56 and tending to pivot lever 50 about the axis of eccentric pin 84 changed direction from counterclockwise to clockwise, which immediately caused lever 50 to pivot in a clockwise direction about the axis of eccentric pin 84 until the periphery of disc 42 engaged the periphery of drive wheel 46.

Following such engagement, the force of spring unit 56 overrides that of spring 80 in imparting further clockwise pivotal movement to crank-like member 54. This initially results in the trailing side of yoke 70 being brought into contact with stud 72, as is indicated in FIG. 3. As is shown in FIG. 4, the further clockwise movement of member 54 carries disc 42 about the circumference of wheel 46 and into peripheral engagement with spindle 14, this occurring as follower 82 moves along segment S2 and to segment S3 of cam 60". The speed of the cams rotation and the slope of its camming edge segment S2 control the rate of such movement and prevent disc 42 from abruptly engaging spindle 14' and thus prevents any structural damage and/or other detrimental results. The present cam does not, however, control or restrict the precise extent of the aforesaid movement, being prevented from doing so by the deliberately loose connection between stud 72 and yoke 70' of lever 70. FIG. 4 shows stud 72 centered between i and spaced equally from the two legs of yoke 70', which is the position normally occupied by it when no spindle misalignments exist and when cam 60 has rotated sufficiently to bring its camming edge segment S3 into engagement with follower 82. If some spindle misalignment should exist, stud 72 would be spaced more closely to one or the other of the opposing legs of yoke 70', but the desired engagement of disc 42 with spindle 14 would, however, still occur and would still be of a suitable force-magnitude which is predetermined by the resilient characteristics of spring unit 56.

Upon engagement therewith, disc 42 now promptly halts and then reverses the normal winding rotation of spindle 14', as indicated by the directional arrow in FIG. 4, the associated drive tape 30 (FIG. 1) merely slipping upon the spindle whirl at such time. The possibility of uneven and/or excessive wearing of its peripheral band 42 is lessened by disc 42 being in a state of rapid rotation, or pre-rotation, at the time of its initial engagement with the spindle. This pre-rotation also contributes, together with the previously noted non-abrupt nature and controlled force-magnitude of the engagement, to the gentle smoothness of the halting and reversing of the spindles winding rotation. Reversal of the spindles rotation is realized rapidly, but without the generation of vibratory or other disruptive forces which might unseat the bobbin therefrom.

After being maintained in its FIG. 4 position for so long as reverse rotation of spindle 14' is desired, disc 42 is moved about the periphery of the spindle to a position, shown in FIG. 5, wherein it is out of engagement with drive wheel 46. As soon as disc 42 passes out of engagement with drive wheel 46, drive tape 30 (FIG. 1) once again drives spindle 14' in a winding direction. Disc 42, now freely rotatable, permits such spindle rotation, and is itself drivingly rotated by it in the counterclockwise direction indicated by the arrow in FIG. 5, but only for the fractional part of a disc revolution necessary to bring end 92" of hub slot 92 (FIGS. 6 and 7) into engagement with the pin 90 carried by shaft 44. Such pin engagement prevents further counterclockwise rotation of disc 42, which in turn then halts the winding rotation of spindle l4 and maintains the spindle stationary with tape 30 merely slipping about its whirl (not shown) until just prior to completion of the remainder of the piecing operation. With some piecing techniques or procedures, it might not be desirable to permit spindle 14' to undergo a limited number of revolutions in a winding direction, following reverse rotation thereof, in the manner described above. In that event the hub means interconnecting disc 42 and shaft 44 might be modified to prohibit any counterclockwise rotation of the disc.

Movement of disc 42 from its FIG. 4 position and to its FIG. 5 position was initiated by rotation of cam 60" bringing into engagement with follower 82 a camming edge segment S4 causing crank-like member 54 to pivot further about its central axis in a clockwise direction. The change thus produced in the resultant force upon lever 50 caused the same to pivot a few degrees in a counterclockwise direction about the axis of pin 84, so lengthening the distance between the centers of disc 42 and wheel 46 as to move the periphery of the former out of engagement with the latter. Engagement between disc 42 and spindle 14' was meanwhile continuously maintained by spring unit 56.

Shortly prior to final completion of the piecing operation, disc 42 is returned to its original position shown in FIG. 2, such return movement being initiated by counterclockwise pivoting of crank-like member 54 about its central axis as rotationof cam 60 brings its segmentSS into engagement with follower 82. Once lever 50 and spring unit 56 have passed their previously mentioned dead-center position (see FIG. 3), spring unit 56 again assumes control and effects the final return of disc 42 to its position of FIG. 2.

OTHER EMBODIMENTS FIGS. SA-D illustrate various alternate embodiments of the mechanism previously described. The mechanism of FIG. 5A includes a linkage 58A in which the straight arm 70 of the linkage 58 of the first embodiment'is replaced by an arm 97 having a yoke 97' extending angularly therefrom, to assist in proper retention of stud 72 between the legs of the yoke. In keeping with the yoke 70' of the first embodiment, both the width and the length of yoke 97 are sufiiciently greater than the diameter of stud 72 to permit the desired relative movement between the stud and the yoke. In FIG. 5B, the linkage 583 comprises a slotted link 98 pivotally connected at one end to an arm 100 carried by rocker shaft 78, and captively receiving within its elongate slot a stud 102 carried by an arm I04 secured to crank-like member 54. FIG. 5D discloses a somewhat'similar arrangement including a slotted link 106 pivotally connected to an arm 108 carried by rocker shaft 78 and receiving a stud 110 upon an arm 112 secured to member 54. In FIG. 5D, however, link 106 is adapted for abutment with a'stop pin 114 also carried by arm 112, which abutment occurs during return movement of disc 42 from its illustrated position back to its fully retracted position. In FIG. 5C, the linkage 58C comprises loosely interrneshing gear segments 116,118, one of which is secured to member 54 and the other of which is secured to rocker shaft 78.

FIGS. 5A, B and D each also illustrate some of the many modifications possible with respect to the control actuator means of the first embodiment. The spring 80 employed in the first embodiment to bias follower 82 into engagement with cam 60" is replaced in FIG. 5A by a weight connected to lever 76 by a cable 122 which passes over a pulley 124, and is replaced in FIG. 58 by a piston and cylinder assembly 126 containing a suitable fluid medium to cause the desired biasing force to be to be exerted upon lever 76. A similar assembly (not shown) might, if desired, be mounted between pin 57 and stub shaft 44, in lieu of the spring cartridge unit 56 of the first embodiment. Another unillustrated modification would be to provide cam 60" with a groove-type camming surface effective to captively maintain follower 82 in engagement therewith without the assistance of any follower biasing means. Still another possible modification is shown in FIG. 5D, wherein the cam and follower assembly of the first embodiment is replaced by a control actuator including a hydraulic piston and cylinder assembly 128, the rod component of which is pivotally connected to lever 76, and a four-way solenoid valve having suitable connections 132,134 with both hydraulic-fluid and electrical-control circuits (not shown). The electrical control signals periodically received by valve 130 cause it to so vary the flow of hydraulic fluid to and from assembly 128 as to produce desired movement of lever 76 comparable to that realized in the previously described first embodiment of the control actuator means.

The disclosure herein of various embodiments of the mechanism, in association with a particular piecing apparatus servicing a spinning machine producing Z twist yarn, was for purposes of illustration only and not for purposes of limitation. Other embodiments of the mechanism will be apparent to those skilled in the art, and principals of the invention are also applicable to other types of piecing apparatus and to the servicing of machines spinning S twist yarn. The scope of the invention therefore should be construed only in accordance with the following claims.

That which is claimed is:

1. In an apparatus for servicing a textile spinning frame or like machine having a rotating spindle, the improvement comprising: I

rotatable disc means for controlling the rotation of said spindle when in engagement therewith;

rotational drive means for imparting rotation to said disc means when in driving engagement therewith;

bipivot mounting means having a fixed pivot axis and a movable pivot axis, said bipivot mounting means mounting said disc means for pivotal movement about said axes between desired positions of disc engagement with and disengagement from said spindle and said rotational drive means;

resilient biasing means for biasing said disc means toward at least one of said positions thereof;

and control actuator means loosely connected to said bipivot mounting means for initiating said pivotal movement of said disc means between various ones of said positions thereof.

2. Apparatus as in claim 1, including linkage means providing said loose connection between said control actuator means and said mounting means, said linkage means including a yoke element operatively connected to one of said control means or mounting means, and a stud element operatively connected to the other of said control means or mounting means and loosely received by said yoke element.

3. Apparatus as in claim 1, including linkage means providing said loose connection between said control actuator means and said mounting means, said linkage means including a pair of loosely intermeshing gear segments, one of said segments being operatively connected to said control means and the other of said segments being operatively connected to said mounting means.

4. Apparatus as in claim 1, including linkage means providing said loose connection between said control actuator means and said mounting means, said linkage means including a slotted link operatively connected to one of said control means or mounting means, and a stud element operatively connected to the other of said control means or mounting means and received by said slotted link.

5. Apparatus as in claim 1, wherein said control actuator means includes a rotatable cam element having a camming surface of varying profile, and a follower element mounted for engagement with said camming surface and for movement thereby toward and away from the axis of rotation of said cam element.

6. Apparatus as in claim 5, wherein said camming surface extends along the peripheral edge of said cam element, and further including means connected to said follower element for biasing said follower into engagement with said camming surface.

7. Apparatus as in claim 6, wherein said means biasing said follower comprises a spring element.

8. Apparatus as in claim 6, wherein said means biasing said follower comprises a piston and cylinder assembly.

9. Apparatus as in claim 6, wherein said means biasing said follower comprises a weight and cable assembly.

10. Apparatus as in claim 1, wherein said control actuator means comprises a fluid-operated piston and cylinder assembly.

11. Apparatus as in claim 1, wherein said mounting means mounts said disc member for movement to a first position wherein said disc member is out of engagement with said spindle and said drive means, to a second position wherein said disc member is out of engagement with said spindle and in engagement with said drive means, to a third position wherein said disc member is in engagement with said spindle and said drive means, and to a fourth position wherein said disc member is in engagement with said spindle and out of engagement with said drive means.

12. Apparatus as in claim 1, wherein said rotational drive means includes a drive wheel concentric with said fixed pivot axis, and a drive shaft connected to said drive wheel for continuously rotating the same during operation of the apparatus.

13. Apparatus as in claim 1, includingmeans for limiting rotation of said disc means in a direction opposite to the direction of the rotation imparted thereto by said drive means.

14. In an apparatus for servicing a textile spinning frame or like machine, said apparatus including a rotatable disc member adapted to engage and to control the rotation of a spindle of said machine during servicing thereof, the improvement comprising:

rotational drive means including a driven drive wheel, said drive means imparting rotation to said disc member upon engagement thereof with said drive wheel;

and means mounting said disc member for pivotal movement about two substantially parallel and relatively movable pivot axes into and out of engagement with said spindle and said drive wheel.

15. Apparatus as in claim 14, wherein one of said axes extends through the center-of said drive wheel, and said disc member is mounted by said mounting means for pivotal movement about the other of said axes into and out of peripheral engagement with said drive wheel.

16. In an apparatus for servicing a textile spinning frame or like machine, said apparatus including a member adapted to engage and to control the rotation of a spindle of said machine during servicing thereof, the improvement comprising:

means mounting said member for bi-directional movement between an extended position of engagement with said spindle and a retracted position of disengagement from said spindle, said extended and retracted positions of said member being located upon opposite sides of an intermediate position thereof;

and resilient means for biasing said member when on one side of said intermediate position toward said extended position thereof, and for biasing said member when on the other side of said intermediate position toward said retracted position thereof.

17. Apparatus as in claim 16, including control actuator means loosely connected to said mounting means for initiating movement of said member from said other side and to said one side of said intermediate position thereof, and for thereafter controlling the rate of movement of said member to said extended position thereof.

18. In an automatic yarn piecing apparatus for servicing a textile spinning frame or like machine, said apparatus including a rotatable disc member adapted to engage and to control the rotation of a spindle of said machine during servicing thereof, the improvement comprising:

rotational drive means for imparting said rotation to said disc member when said disc member is in driven relationship therewith;

and means mounting said disc member for movement between a first position wherein said disc member is out of engagement with said spindle and out of driven relationship with said drive means, and a second position wherein said disc member is out of engagement with said spindle and in driven relationship with said drive means, and a third position wherein said disc member is in engagement with said spindle and in driven relationship with said drive means, and a fourth position wherein said disc member is in engagement with said spindle and out of driven relationship with said drive means. 

1. In an apparatus for servicing a textile spinning frame or like machine having a rotating spindle, the improvement comprising: rotatable disc means for controlling the rotation of said spindle when in engagement therewith; rotational drive means for imparting rotation to said disc means when in driving engagement therewith; bipivot mounting means having a fixed pivot axis and a movable pivot axis, said bipivot mounting means mounting said disc means for pivotal movement about said axes between desired positions of disc engagement with and disengagement from said spindle and said rotational drive means; resilient biasing means for biasing said disc means toward at least one of said positions thereof; and control actuator means loosely connected to said bipivot mounting means for initiating said pivotal movement of said disc means between various ones of said positions thereof.
 2. Apparatus as in claim 1, including linkage means providing said loose connection between said control actuator means and said mounting means, said linkage means including a yoke element operatively connected to one of said control means or mounting means, and a stud element operatively connected to the other of said control means or mounting means and loosely received by said yoke element.
 3. Apparatus as in claim 1, including linkage means providing said loose connection between said control actuator means and said mounting means, said linkage means including a pair of loosely intermeshing gear segments, one of said segments being operatively connected to said control means and the other of said segments being operatively connected to said mounting means.
 4. Apparatus as in claim 1, including linkage means providing said loose connection between said control actuator means and said mounting means, said linkage means including a slotted link operatively connected to one of said control means or mounting means, and a stud element operatively connected to the other of said control means or mounting means and received by said slotted link.
 5. Apparatus as in claim 1, wherein said control actuator means includes a rotatable cam element having a camming surface of varying profile, and a follower element mounted for engagement with said camming surface and for movement thereby toward and away from the axis of rotation of said cam element.
 6. Apparatus as in claim 5, wherein said camming surface extends along the peripheral edge of said cam element, and further including means connected to said follower element for biasing said follower into engagement with said camming surface.
 7. Apparatus as in claim 6, wherein said means biasing said follower comprises a spring element.
 8. Apparatus as in claim 6, wherein said means biasing said follower comprises a piston and cylinder assembly.
 9. Apparatus as in claim 6, wherein said means biasing said follower comprises a weight and cable assembly.
 10. Apparatus as in claim 1, wherein said control actuator means comprises a fluid-operated piston and cylinder assembly.
 11. Apparatus as in claim 1, wherein said mounting means mounts said disc member for movement to a first position wherein said disc member is out of engagement with said spindle and said drive means, to a second position wherein said disc member is out of engagement with said spindle and in engagement with said drive means, to a third position wherein said disc member is in engagement with said spindle and said drive means, and to a fourth position wherein said disc member is in engagement with said spindle and out of engagement with said drive means.
 12. Apparatus as in claim 1, wherein said rotational drive means includes a drive wheel concentric with said fixed pivot axis, and a drive shaft connected to said drive wheel for continuously rotating the same during operation of the apparatus.
 13. Apparatus as in claim 1, including means for limiting rotation of said disc means in a direction opposite to the direction of the rotation imparted thereto by said drive means.
 14. In an apparatus for servicing a textile spinning frame or like machine, said apparatus including a rotatable disc member adapted to engage and to control the rotation of a spindle of said maChine during servicing thereof, the improvement comprising: rotational drive means including a driven drive wheel, said drive means imparting rotation to said disc member upon engagement thereof with said drive wheel; and means mounting said disc member for pivotal movement about two substantially parallel and relatively movable pivot axes into and out of engagement with said spindle and said drive wheel.
 15. Apparatus as in claim 14, wherein one of said axes extends through the center of said drive wheel, and said disc member is mounted by said mounting means for pivotal movement about the other of said axes into and out of peripheral engagement with said drive wheel.
 16. In an apparatus for servicing a textile spinning frame or like machine, said apparatus including a member adapted to engage and to control the rotation of a spindle of said machine during servicing thereof, the improvement comprising: means mounting said member for bi-directional movement between an extended position of engagement with said spindle and a retracted position of disengagement from said spindle, said extended and retracted positions of said member being located upon opposite sides of an intermediate position thereof; and resilient means for biasing said member when on one side of said intermediate position toward said extended position thereof, and for biasing said member when on the other side of said intermediate position toward said retracted position thereof.
 17. Apparatus as in claim 16, including control actuator means loosely connected to said mounting means for initiating movement of said member from said other side and to said one side of said intermediate position thereof, and for thereafter controlling the rate of movement of said member to said extended position thereof.
 18. In an automatic yarn piecing apparatus for servicing a textile spinning frame or like machine, said apparatus including a rotatable disc member adapted to engage and to control the rotation of a spindle of said machine during servicing thereof, the improvement comprising: rotational drive means for imparting said rotation to said disc member when said disc member is in driven relationship therewith; and means mounting said disc member for movement between a first position wherein said disc member is out of engagement with said spindle and out of driven relationship with said drive means, and a second position wherein said disc member is out of engagement with said spindle and in driven relationship with said drive means, and a third position wherein said disc member is in engagement with said spindle and in driven relationship with said drive means, and a fourth position wherein said disc member is in engagement with said spindle and out of driven relationship with said drive means. 